Fire-proof compound and sheet



106. COMPOSITIONS,

U ITED STATES Cross Reference are, 935 PATENT, OFFICE.

NATHANIEL-O. FOWLER, or BOSTON, MASSACHUSETTS, AsSIeNdR, BY MESNE ASSIGNMENTS, TO THE INDESTRUGTIBLE SAFE PANY, OF'WEST VIRGINIA.

Ann FIRE PROOF ooM- FlRE-PROOF CQMPOUNDFAND S H E ET.

SPECIFICATION formingpart of Letters Patent No. 288,935, dated November '20, 1883.

Application filed June 28,1883. (Specimens) l 10 all whom it may concern:

Be it known that I, NATHANIEL Fowter-of-paris, (gypsum,) asbestus finely fibrilized, lamp-black, and finely-ground pumice stone. The proportions are to be taken by-rela- 'tive bulk or cubic measurement, and not by weight.

The invention also consists in rendering the mixture sufficiently consistent by means of water, and then running the mass off onto a table or other suitable surface'in as thick sheets and of the size required. When these sheets are dry, they may be used in the construction of fire-proof boxes, for the lining of fire-proof safes, 'or for other like purposes. 1

The proportions for, the mixture shouldbe ascertained as abovedescribed, and should be substantially as follows: about seventy per cent-um of calcined plaster-of-pa'ris, about twenty per centum of asbestus, five per centum (more or less) of lamp-black, and about five per centum of pumice-stone.

Though asbestns is fire-proof, its principal value in this compound consistsin its adhesive quality. Being, as it is, a fibrous material, it gives strength to the entire mass, and prevents the crumbling which might come from jarring or other causes.

Lamp-black is combustible when subjected to a high degree of heat, but is of value in this compound because of the fact that when evenly and carefully mixed therewith it renders the whole mass porous, and it is a wellknown fact that an infinite number of air-cells increases very largely the capacity of a fabric to resist the action of heat.

Other articles-such as finely-ground Sawd ust, br wood imp-could be used; but lampt EXAMINER black is preferable because of its infinite'fine- 1 ness, and thus its usefulness in producing an infinite number of air-cells. Alarger proportion of lamp-black than five per cent. could be used; but as this material may be destroyed by ahigh temperature, as I have stated, it is better that not more than about five per cent.

of the entire bulk be employed, for were this moderate percentage of lamp-black to be destroyed, the capacity of the rest of the mass to successfully resist the action of heatwould not be materially lessened.

Sheets may be produced as above described, and they may be jointed one to another by nioisteuin g their edges with water-preferably warm water.

While the mass is in a plastic state it can'be molded into any shape desired, or it maybe filled into the hollow sides of a safe or box. -Having thus fully described my invention and the manner of carrying the same into ef fect, what I claim as new, and desire to secure;

by Letters Patent, isp 1. In combination, calcined plaster-of-p'aris,

finely -fibrilized asbestus, lamp black, and

finely-ground pumice-stone, the whole compounded in a dry State, and in substantially the proportions described, said proportions'to be ascertained upon the basis of bulk, substantially as described.

,2. As an article of manufacture, sheets of fire-proof material produced by compounding, when in a dry state, calcined plaster-of-paris, finely;fibrilized asbestus, lamp-black, and pumice-stone, in substantially the proportions and in the mannerdescribed, such dry compound to bewet with water to a suitable consistency, then runoff upon a level surface into the thickness and size of sheets desired, and allowed dry, all substantially as described.

'GLARKEFOWLER.

' NATHANIEL I Witnesses:

' -FRANOIS W. BoUTWELL,

-' FLoRENoE L. EMERY. 

